Fix to run on node.js

Switch to `@kmamal/sdl`.

Author: tyfkda

.gitignore

@@ -16,3 +16,5 @@ typings
 /release
 
 /nodejs/nesemu.js
+/nodejs/package-lock.json
+*.LICENSE.txt

nodejs/.babelrc

@@ -1,5 +1,11 @@
 {
   "presets": [
-    ["env", {"module": false}]
+    [
+      "@babel/preset-env",
+      {
+        "useBuiltIns": "usage",
+        "corejs": 3
+      }
+    ]
   ]
 }

nodejs/README.md

@@ -3,15 +3,12 @@ for node.js
 
 ### Requirement
 
-  * Node.js < 9 ([node-ffi does not build with NodeJS 9.x on Linux · Issue #451 · node-ffi/node-ffi](https://github.com/node-ffi/node-ffi/issues/451))
-  * Python 2 ([Support for Python 3 · Issue #1337 · nodejs/node-gyp](https://github.com/nodejs/node-gyp/issues/1337))
   * SDL2
 
 
 ### Set up
 
-  1. Set up Node.js < 9, and Python 2.x
-  2. Install SDL2
+  1. Install SDL2
 
 , then
 

nodejs/package.json

@@ -5,23 +5,24 @@
   "main": "nesemu.js",
   "scripts": {
     "start": "npm run build",
-    "build": "webpack",
-    "exec": "node nesemu.js",
+    "build": "npx webpack",
+    "exec": "npx node nesemu.js",
     "test": "echo \"Error: no test specified\" && exit 1"
   },
   "author": "tyfkda",
   "license": "Unlicense",
   "devDependencies": {
-    "babel-core": "~6.26.3",
-    "babel-loader": "~8.0.2",
-    "babel-preset-env": "~1.7.0",
-    "ts-loader": "~5.2.1",
-    "typescript": "~3.1.1",
-    "webpack": "~4.20.2",
-    "webpack-cli": "~3.1.2"
+    "@babel/core": "~7.21.8",
+    "@babel/preset-env": "~7.21.5",
+    "@babel/register": "~7.21.0",
+    "@types/node": "~18.16.3",
+    "ts-loader": "~9.4.2",
+    "typescript": "~5.0.4",
+    "webpack": "~5.82.0",
+    "webpack-cli": "~5.0.2"
   },
   "dependencies": {
-    "jszip": "~3.1.3",
-    "node-sdl2": "git+https://github.com/tyfkda/node-sdl2.git#master"
+    "@kmamal/sdl": "~0.7.4",
+    "jszip": "~3.10.1"
   }
 }

nodejs/src/@types/audio_context/index.d.ts

@@ -1,3 +1,5 @@
+declare function __non_webpack_require__(fn: string)
+
 interface AudioNode {
   readonly context: AudioContext
 
@@ -30,14 +32,16 @@ interface DelayNode extends AudioNode {
   delayTime: AudioParam
 }
 
+interface ScriptProcessorNode extends AudioNode {
+  onaudioprocess: Function
+}
+
 interface AudioDestinationNode extends AudioNode {
 }
 
 interface AnalyserNode extends AudioNode {
 }
 
-type ScriptProcessorNode = any
-declare const ScriptProcessorNode: ScriptProcessorNode
 type AudioWorkletNode = any
 declare const AudioWorkletNode: AudioWorkletNode
 
@@ -53,4 +57,7 @@ interface AudioContext {
   createDelay(): DelayNode
   createAnalyser(): AnalyserNode
   createScriptProcessor(size: number, a: number, b: number): ScriptProcessorNode
+
+  // Additional method:
+  update(dt: number): void
 }

nodejs/src/audio_context.ts

@@ -1,9 +1,4 @@
-declare function __non_webpack_require__(fn: string)
-
-import {audio as SDLAudio} from 'node-sdl2/lib/audio'
-
-const NS = __non_webpack_require__('node-sdl2')
-const SDL_audio = NS.require('SDL_audio')
+const sdl = __non_webpack_require__('@kmamal/sdl')
 
 class AudioParam {
   public value = 0
@@ -44,8 +39,6 @@ export class PeriodicWave {
 
 const enum OscillatorType {
   NONE,
-  // SQUARE,
-  // SINE
   TRIANGLE,
   SAWTOOTH,
   PERIODIC_WAVE,
@@ -66,8 +59,11 @@ export class OscillatorNode extends AudioNode {
   }
 
   setPeriodicWave(_wave: PeriodicWave): void {
-    this.oscType = OscillatorType.PERIODIC_WAVE
+    // this.oscType = OscillatorType.PERIODIC_WAVE
     //this.wave = wave
+
+    // TODO: Calculate wave.
+    this.oscType = OscillatorType.TRIANGLE
   }
 
   public sample(counter: number, sampleRate: number): number {
@@ -119,8 +115,65 @@ export class DelayNode extends AudioNode {
   }
 }
 
+class OutputBuffer<T> {
+  constructor(public buffer: T[]) {}
+
+  public getChannelData(index: number) {
+    return this.buffer[index]
+  }
+}
+
+export class ScriptProcessorNode extends AudioNode {
+  private index = 0
+  private onaudioprocess: any = (_) => {}
+  private outputBuffer: OutputBuffer<Float32Array>
+  private ev: {outputBuffer: OutputBuffer<Float32Array>}
+
+  public constructor(context: AudioContext, size: number, _inputChannels: number, outputChannels: number) {
+    super(context)
+    const buffer = [...Array(outputChannels)].map(_ => new Float32Array(size))
+    this.outputBuffer = new OutputBuffer<Float32Array>(buffer)
+    this.ev = {
+      outputBuffer: this.outputBuffer,
+    }
+  }
+
+  public sample(_counter: number, _sampleRate: number): number {
+    if (this.index === 0) {
+      this.onaudioprocess(this.ev)
+    }
+    const value = this.outputBuffer.buffer[0][this.index]
+    if (++this.index >= this.outputBuffer.buffer[0].length) {
+      this.index = 0
+    }
+    return value
+  }
+}
+
 class AudioDestinationNode extends AudioNode {
   private time = 0
+  private playbackInstance: any
+  private buffer: Buffer
+  private f32Array: Float32Array
+
+  public constructor(context: AudioContext) {
+    super(context)
+    const channels = 1
+    this.playbackInstance = sdl.audio.openDevice({type: 'playback'}, {
+      channels,
+      buffered: 512,
+    })
+
+    const frames = (1.0 / 60 * this.sampleRate) | 0
+    this.buffer = Buffer.alloc(frames * 4 * channels)
+    this.f32Array = new Float32Array(this.buffer.buffer)
+
+    this.playbackInstance.play()
+  }
+
+  public get sampleRate(): number {
+    return this.playbackInstance.frequency
+  }
 
   public fillBuffer(array: Float32Array) {
     const len = array.length
@@ -142,28 +195,22 @@ class AudioDestinationNode extends AudioNode {
   public sample(_counter: number, _sampleRate: number): number {
     return 0
   }
+
+  public update(_dt: number) {
+    this.fillBuffer(this.f32Array)
+    this.playbackInstance.enqueue(this.buffer)
+  }
 }
 
 export class AudioContext {
-  private audio: SDLAudio
   private destination  = new AudioDestinationNode(this)
 
   public get sampleRate(): number {
-    return this.audio.spec.freq
+    return this.destination.sampleRate
   }
 
-  public constructor() {
-    this.audio = NS.audio.create()
-    const options = {
-      freq: 48000,
-      channels: 1,
-      format: SDL_audio.SDL_AudioFormatFlag.AUDIO_F32,
-      samples: 512,
-    }
-    this.audio.openAudioDevice(options, (arrayBuffer: ArrayBuffer) => {
-      const array = new Float32Array(arrayBuffer)
-      this.destination.fillBuffer(array)
-    })
+  public update(dt: number): void {
+    this.destination.update(dt)
   }
 
   public createGain(): GainNode {
@@ -178,6 +225,10 @@ export class AudioContext {
     return new DelayNode(this)
   }
 
+  public createScriptProcessor(size: number, a: number, b: number): ScriptProcessorNode {
+    return new ScriptProcessorNode(this, size, a, b)
+  }
+
   public createPeriodicWave(real: Float32Array, imag: Float32Array): PeriodicWave {
     return new PeriodicWave(real, imag)
   }